Flow cytometry is one of the most widely used and indispensable techniques for the analysis and isolation of specific cell populations. The CFAR Flow Cytometry Core was established in 2003 with initial seed funds from the CFAR grant to provide CFAR investigators with improved access to advanced flow cytometry equipment and techniques. The CFAR Core is unique among the flow cytometry resources at Einstein in providing biohazard containment for carrying out analysis and sorting of samples requiring Biosafety Level-2 or higher precautions, and is thus a major resource for work involving HIV and a variety of AIDS-related opportunistic pathogens. The CFAR Flow Cytometry Core provides CFAR investigators with ready access to a variety of advanced instruments for analytical flow cytometry and cell sorting, and extensive technical expertise and assistance for performance of established flow cytometry techniques and implementation of new technologies in this area. In the four years since its inception, the Core has grown substantially with regard to space, equipment and personnel. This reflects the important role that this core facility has played in CFAR related research projects, and also the considerable institutional support that underscores the value added features of the Core. The activities of the Core are organized according to the following four specific aims: Aim 1. To maintain the necessary research infrastructure needed for flow cytometry studies, with appropriate biosafety containment safeguards. Aim 2. To maintain cutting edge capabilities by regularly updating existing flow cytometry resources and introducing new equipment and techniques in a timely manner. Aim 3. To provide convenient and cost-effective access to equipment and technical expertise for the performance and interpretation of flow cytometry. Aim 4. To provide education and training to assist CFAR investigators in the implementation of new and established flow cytometry techniques. RELEVANCE: Flow cytometry allows researchers to study many properties of cells or micro-organisms and rapidly gather information that is crucial to understanding disease processes in animal models and human subjects. The CFAR Flow Cytometry Core supports instruments and personnel that are required for this type of essential research, and organizes these resources in a centralized facilty that provides access for a large number of investigators working on a wide range of problems relevant to HIV infection and AIDS.